Isovaleric acidemia is a type of organic acidemia for which the earliest definite diagnosis was attained. It features an autosomal recessive inheritance, with the onset of age varying from newborn to adulthood. The clinical manifestations are complex and variable, which include feeding difficulty, vomiting, lethargy, coma, metabolic acidosis, sweaty feet odor and mental retardation. The mortality and mobility rates of isovaleric acidemia are quite high, and early diagnosis and rational treatment can significantly improve the prognosis. This article has provided a summary for the current understanding and research progress on isovaleric acidemia.